Super Nerd Sunday Presents: Making Mistakes in Tower Defense Games!

The Tower Defense genre is downright venerable at this point, with its roots in the earliest RTSes.  But the Action Tower Defense subgenre is actually quite new.  Elements of it began appearing in Tower Defense conversions in Warcraft 3, and even Plants vs Zombies had some action bits in its tower defense mix, but the genre didn’t really begin to solidify until titles like Sanctum and Orcs Must Die came to be, with their fast moving, hard hitting central “builder” figures and viable strategies and achievements in place for completing maps without the use of a single “tower” like construct.  And there’s something about this formula that manages to make tower defense more...tower defensey than every before.

See, in a conventional Tower Defense game you’re really just thinking about how an array of towers can destroy enemies as efficiently as possible.  The more efficient your deployment, the more capable you are of responding to follow-up waves that force you to change your strategy.  Tower Defense games, ergo, rely heavily on replayability and feature steep learning curves that often turn on learning how to use a handful of critical elements and learning how and when to avoid using certain elements in order to conserve resources.  The end result of this learning curve/resource allowance issue is that you, as the tower defense mastermind, lose control of the situation you’re in very, very quickly, not via the sort of war of attrition you wage in tower defense games, but in a single, often underwhelming moment where you simply didn’t build the right tower (or the right kind of tower) in the right place.

That big heavy enemy you were fighting that got through and reached the fail-point (what I call the point in a tower defense map where enemies must not reach, upon pain of losing points or worse, the round) would’ve been stopped if only you built the tower that shocks enemies for large amounts of damage and a brief stun, which is in turn the tower that you needed to back up with a tiny flamethrower tower, effective against hordes of enemies but ineffective against single large targets, the want of which let that horde of tiny critters get through to your fail point.

This makes for a painful sort of trial and error system, where mistakes, by merit of build times and build costs, cannot be corrected at the last minute and where a single mistake (not forecasting waves correctly, or failing to comprehend the mechanics behind the towers, many of which may or may not be new) will lead to an outright failure.  That can often mean beginning an entire mission or round over again, potentially losing all your hard won progress and your carefully arrayed towers because of one mistake.

The mechanic of having an avatar on the field who can mete out punishment changes the whole game, however.  This avatar doesn’t just give you the opportunity to kill enemies with your own filthy, blood caked hands: it also provides you with the ability to dexterously respond to unexpected circumstances and make up for gaps in your towers or traps or whatever.  That means that you can either learn how to compensate for mechanics that either don’t work or are marginally effective (or redundant) or just deal with a particularly messy round where your towers fail in a particular way.

This translates to a faster paced, more accident prone kind of play, a format that permits you to make mistakes, learn from them and keep on rolling.  That means a more accumulative style of play as you push forward, an accumulative style of play that doesn’t have to end just because you met a troll for the first time and it battered through the defenses you set up, or because you didn’t understand how wall grinders worked for the longest time or didn’t see the value of brimstone tiles until the third to last level.

Orcs Must Die 2 is the pinnacle of demonstrating this philosophy of actually allowing players to learn from their mistakes.  It permits players to generate autonomous death-dealing passages that shred orcs without even the slightest attention from their avatar, or to generate screening systems that eliminate some or most orcs, allowing players to position their avatars at critical junctures to deal with any kind of runoff.  Paired with a generous allowance system that permits you to let almost three dozen orcs through your defenses, it represents an ethos that tower defense has always hinted at, but never really permitted its players to engage with before.

See, in Orcs Must Die 2, nothing is permanent.  If you place a trap or a hireling during a battle and you figure out that you did it wrong, you can remove them for a full refund (or partial refund, in the case of damaged hireling) during the downtime between waves and put those orcbux to use placing new, more useful, better positioned trap.  That means that mistake you made or experiment you tried that didn’t quite work won’t trash your game if it doesn’t pay out.  And this is just the structure within the course of play itself.  It’s not that there aren’t any stakes, it’s that object-permanence isn’t a concern and, as a result, the field is never really set.

This philosophy extends to the abilities you purchase between the various stages of the game as well.  There’s never an occasion where you won’t be able to undo a particular purchase or decision that you make with skulls, the currency used for purchasing upgrades.  If you find out that those really cool looking ceiling mounted auto-crossbows are shit, for example, you can get rid of them.  If you realize that dwarves are, in fact, quite useless (as I did) you can get back the skulls you sank into making them a viable defensive option.  The end result is a system that is constantly being rewritten, that encourages you, indeed even revels in you taking advantage of and exploring each and every element of the game in a way that expands the concept of what it means to be a tower defense game.  Consequences are light.  Failure is to be expected, especially as the game leads you towards playing in an endgame format where you have to lose eventually (Endless) or where losing is a distinct possibility (an impressively challenging Nightmare difficulty caps off the game itself).  Orcs Must Die 2 wants you to fail, it acknowledges that failure is a part of Tower Defense games in general, and moreover it wants you to be okay with failing.

And it all comes back to that avatar.  All of the systems that allow you to buy and sell towers, that allow you to spontaneously rewrite the upgrades you’ve selected, all of them feed back to the fact that you are primarily playing the game as a man with a gun who is picking off the orcs that towers miss.  This mechanic doesn’t so much revolutionize the way tower defense games play as it accentuates the ethos behind them that trial and error is a tremendous part of the game, a part of learning and winning a fight.  It just does so without breaking stride or forcing a restart: it presents a model of tower defense play where making mistakes during play doesn’t need to interrupt the game itself, allowing players to use their learning opportunity immediately instead of dealing with the stress and frustration of restarting a match.

It’s a good thing.